Known in the art is a welder's training simulator comprising mechanisms modeling the motion of a weldpool relative to a simulated member and the decrease in the length of a rod electrode, and circuits producing appropriate signals and recording the actions of the worker being trained. In this trainer the welded member simulator includes a movable target simulating a weldpool and a photoelectric cell that can move along the joint by a straight line or zigzag-like. The electrode holder simulator is equipped with an electrode simulator, a transducer responding to the arc gap length and an electrode simulator setting angle sensor. The end of the electrode simulator is provided with a protruding adapter made of a transparent material which simulates the length of the arc between the electrode simulator end and the simulated welded member, said electrode simulator having a light source for illuminating said adapter. The adapter is capable of moving to switch on a sensor having a permissible arc gap length as a preset parameter.
This sensor is a switch having a pair of contacts while the adapter moves so tht the movable contact makes connection with any of the above mentioned contacts located at both ends of its path, said pair of contacts being controllable with respect to the movable contact of the adapter for changing the parameters. The trainer also comprises a signal lamp, an audio-frequency generator simulating light and noise background of an electric arc welding process and sending an alarm signal on breaking a preset length of the arc gap (cf. British Pat. No. 1,455,972, IPC G09 B 9/00, 1976, Harvey Bordsen Schow and Maeyl Abrams).
The known trainer has a disadvantage consisting in incorrect simulation of the welding process due to utilization of the threshold sensor of the arc gap length having a mechanical contact between the electrode simulator end and the welded member simulator. This results in working out incorrect technique of tought persons and reduces the quality of their training.
Also known in the art is a trainer, which comprises a helmet with built-in headphones an electrode simulator with a holder, equipped with a device sensing the angular position of the electrode simulator, a drive simulating the electrode fusion, a permanent magnet at the end of the electrode simulator, a target unit with a movable carriage having a drive and simulating a movable weldpool. Mounted on the carriage are Hall generators recording the length of the arc gap, deviation from the target center and the speed of the end of the electrode simulator, and a signal lamp simulating the arcing. The trainer also comprises a control unit which records the disturbance of the preset length of the arc gap, angular position of the electrode simulator and speed of the end of the electrode simulator (cf. U.S. Pat. No. 4,124,944, IPC G09 B 19/24, published in 1978, Blair Bruce A.).
The disadvantage of the above trainer is that it simulates only the ambient factors accompanying the process of welding, devices senses the length of the arc gap and the angle of slope of the electrode simulator are threshold sensors, which have poor noise immunity against external electromagnetic fields; the accuracy of indication of the device sensing the arc gap length depends on the angle of slope of the electrode simulator and this results in working out incorrect psychomotor habits of the welder being trained.
Known in the art is a trainer disclosed in USSR inventor's certificate No. 1,038,963, IPC G09 B 19/24, published in 1983, the inventors: V. V. Vasiliev, S. H. Danilyak, N. A. Ropalo.
This trainer comprises a helmet with built-in headphones, an electrode simulator with a holder, a control unit, a unit for modeling the heat balance of a welding process, a target unit, and a unit for recording the space position of the electrode; the electrode simulator is made in the form of a hollow cylinder containing the radiating and receiving elements of devices sensing the arc gap length, slope angle of the electrode and its deviation from the target center; the outputs of said elements are connected to the electrode space position recorder connected to the control unit and to the unit for modeling the heat balance.
Also known in the art is a trainer disclosed in USSR inventor's centificate No. 980124, IPC G09 B 18//24, published in 1982, inventors: B. E. Paton, G. E. Pukhov, V. V. Vasiliev, V. A. Bogdansky.
This trainer comprises a helmet with built-in headphones, an electrode simulator with a holder, a drive for simulation of electrode end fusion, a permanent magnet at the electrode end, a target unit with a movable carriage containing a lamp with two filaments and provided with a drive for simulation of a movable weldpool, and a unit building up a heat balance electronic model. Mounted on the carriage are Hall generators for recording the arc gap length, deviation of the end of the electrode simulator from the target center and speed of the end of the electrode simulator; a signal lamp whose first filament is used for simulation of the arcing while the second filament is used for simulation of the thermal processes taking place in the weldpool; said lamp is connected to the enthalpy signal output of the unit providing the heat balance electronic model. The trainer includes a control unit responding to disturbance of a preset value of arc gap length, angular position of the electrode simulator, its speed and the weldpool thermal conditions.
These two trainers are disadvantageous in a low efficiency of the training and limited functional possibilities since the trainer does not provide simulation of such factors of a real welding process as a change of the size and brightness of the weldpool in the process of welding simulation, simulation of grooving of the simulated welded components with a possibility of changing the weldpool parameters, simulation of flying sparks and simulation of a welding joint image which might be used for estimating the path of movement of electrode simulator end and the quality of the conducted simulated welding process, as well as burn-out and incomplete penetration. The known trainers are based on strictly linear configuration of the joint and they cannot be used for training to the art of making curvilinear and multipass joints. The known trainers are intended for teaching the welding with stick electrodes and they cannot be used for training of a welder to employ electrode wire in an inert gas medium because a hand tool simulator is not provided. This restricts the field of application of the known trainers and their functional facilities. The trainers cannot operate under self-teaching conditions when the weldpool tracks the position of the electrode simulator end; instead, the trainers provide a program training mode when the welder follows the position of the weldpool with the electrode, and this also limits the possibility of application of the trainers for checking the professional ability and skill of welders.